Instrument Change Bug?

Dorico Error.png
Could anyone explain what is happening here and how to fix it? (This is an instrument switch)

The error is seen in the Engrave window and Page View in the Write window… The error persists when exported to PDF.

Undoubtedly someone will be able to explain what’s going on and how to fix it, but (much) less likely without an actual project.
As per the pinned guidelines here: https://www.steinberg.net/forums/viewtopic.php?f=246&t=155802 please post a project, not a picture.

The project is too large to upload here. But here is a google drive link:

https://drive.google.com/file/d/1NjvNCTl33GERUwh4HUyoeSzNwDn2xAd_/view?usp=sharing

Just condensed it. Here is a copy of the Dorico Project. I notice when you delete the strings the problem goes away… but that still doesn’t explain why it happened (and I want to keep the strings?).
Dorico Instrument Change BUG.zip (442 KB)

I can’t explain exactly why this is working the way it’s working, but if you turn this value up by even just 1% (to 61%) the system stops spreading itself to cover the entire page, and the problem goes away.

You’re right that fixes the bug. I still hope the developers on Dorico can figure out why this happens though because when I return to 60% (or below) the problem comes back, and I’m sure I don’t want to be stuck above a certain justification just so I don’t trigger a bug.

We’ll look into this and come back to you.

Thank you Daniel, as always.

We’ve looked into this problem, and the problem is caused by the fact that your Horn 1.3 player is a section player, and is holding more than one instrument. This isn’t supposed to be possible, and presumably you’ve done it by dragging an instrument from one player to another, which is something we will tighten up in future versions to prevent you from getting into trouble in this way.

What you’ll need to do is add a new solo player and drag both of the instruments from the section player to that new solo player, then delete the old and now empty section player.

Oh that’s actually very interesting. I’ll be sure to do it that way in the future. Thanks Daniel!